1. Field of Invention
The present invention relates to the biomaterials field, and more particularly to a process for preparing compounds of chitosan saccharified with aminosugar.
2. Description of Related Arts
Chitosan is a natural biological polysaccharide. Due to the advantages of abundance, biodegradability, good stability and good bioaffinity, chitosan is a satisfactory resource for developing biomedical materials. Chitosan has earned much attention in research of facultative molecular materials. In the current researches, there have been reports about preparing conjugate of chitosan grafted with galactose by method of covalent bonding, e.g., covalently bonding polyvinyl alcohol (PEG) and galactose to chitosan molecule in turn. The compound material formed can not only specifically recognize receptor protein on surface of hepatocyte, but also carry hydrophobic drugs. However, it takes complicated steps to prepare the compound mentioned above, and the compound is unstable because its O-glycosidic bond degrades easily in vivo. There have also been reports about compound materials formed by covalently bonding polyvinyl alcohol (PEG) to chitosan molecule. The compound materials are sensitive to pH, but have bad carrying capability. There have also been reports about glycosylation modification to chitosan with galactose for introducing galactose into chitosan molecule, so as to form chitosan compound. However, molecules of the chitosan compound lack of hydrophobic groups, and therefore has drawbacks as carrier materials in application. Obviously, it is important to prepare stable carrier materials which have high carrying capability to hydrophobic drugs in the field of pharmaceutical preparations.